The precise production of 4.5 μm off-axis first order FBG in an SMF-28e fiber through femtosecond laser direct writing is demonstrated. The off-axis FBG potential as sensing head for torsion sensing was successfully explored.
Quandong HuangYongqin YuShuangchen RuanXuejin LiXue ChenYufeng ZhangWen ZhouChenlin Du
Duarte ViveirosVítor A. AmorimJoão M. MaiaSusana SilvaOrlando FrazãoP. A. S. JorgeLuís A. FernandesP. V. S. Marques
Shuhui LiuChenxi HuangNingliang LiuHailiang ZhangPeixiang LuPerry Ping Shum
Rongsheng LiuPengtao LuoXingyong LiFengyi ChenRui ZhouXueguang Qiao